Absolute Kinetic Studies of Carbene Reactions

卡宾及其反应中间体的激光研究 将进行闪光光解。光谱和动力学 测量这些高活性中间体在溶液中的 将被制造。研究项目将包括调查 （1）亲核卡宾的性质;（2） 卡宾/金属盐反应（类卡宾形成）的动力学; (3)“推拉”卡宾和吡啶基的性质 （4）氟和甲氧基的影响 调节分子内卡宾的取代基 重排;和（5）氧卡宾的断裂， 碳阳离子这些研究将特别重要， 提供对反应的洞察和理解， 其特征在于低活化能势垒。 %%% 有机动力学计划的这笔赠款支持 罗伯特·A教授的工作。罗格斯大学的莫斯 大学这些研究将围绕 卡宾的产生和反应，卡宾是 含有两个而不是四个形式键的碳原子 在稳定的碳化合物中发现的化学键。卡宾是 反应性中间体的寿命非常短。排专用闪光 激光技术将被用来观察这些反应 中间体，并研究它们反应的速率。 卡宾可以进行反应，得到其他反应性的 中间体的例如，卡宾可以与锂反应， 氯化物生成加合物，称为类卡宾， 四个键的正常互补。通过适当的替代， 卡宾可以产生另一种反应性中间体，碳阳离子， 它含有一个有三个键的碳和一个净单位的 正电荷这些反应将为研究 有机合成中的一些重要的活性中间体 化学.

A study of carbenes and related reactive intermediates by laser flash photolysis will be conducted. Spectroscopic and kinetic measurements of these highly reactive intermediates in solution will be made. The research projects will include investigation of: (1) the properties of nucleophilic carbenes; (2) the kinetics of carbene/metal salt reactions (carbenoid formation); (3) the properties of "push pull" carbenes as well as pyridyl and pyridinium carbenes; (4) the effects of fluoro and methoxy substituents in modulating intramolecular carbene rearrangements; and (5) the fragmentation of oxycarbenes to carbocations. These studies will be of particular importance in providing insight and understanding for reactions that are characterized by low activation energy barriers. %%% This grant from the Organic Dynamics Program supports the continuing work of Professor Robert A. Moss at Rutgers University. These studies will be centered around the production and reactions of carbenes, which are species that contain a carbon atom with two formal bonds rather than four bonds as found in stable carbon compounds. Carbenes are reactive intermediates that are very short-lived. Special flash laser techniques will be employed to observe these reactive intermediates and to study the rate at which they react. Carbenes can undergo reaction to give other reactive intermediates. For example, carbenes can react with lithium chloride to generate an adduct called a carbenoid with the normal complement of four bonds. With appropriate substitution, carbenes can give another reactive intermediate, a carbocation, which contains a carbon with three bonds and a net one unit of positive charge. These reactions will provide a means to study some of the important reactive intermediates in organic chemistry.